Gikfun Non-Contact Liquid Level Sensor Water Level Switch XKC-Y25-NPN for Arduino EK1954

Gikfun Non-Contact Liquid Level Sensor Water Level Switch XKC-Y25-NPN for Arduino EK1954

Gikfun 12V DC Dosing Pump Peristaltic Dosing Head with Connector For Arduino Aquarium Lab Analytic Diy AE1207

CQRobot TDS (Total Dissolved Solids) Meter Sensor Compatible with Raspberry Pi/Arduino Board. for Liquid Quality Analysis Teaching, Scientific Research, Laboratory, Online Analysis, etc.